The scientific demonstration that some diseases are due to the growth and development of certain specific micro-organisms in the human body dates from about twenty years ago, although the theory of such causal relation is much older. Since 1880 it has been proved that anthrax, Asiatic cholera, cerebro-spinal meningitis, diphtheria, one form of dysentery, erysipelas, glanders, gonorrhœa, influenza, certain epidemics of meat-poisoning, pyæmia and suppuration in general, pneumonia, tetanus, relapsing fever, tuberculosis, bubonic plague, and typhoid fever are due to minute vegetable organisms known as bacteria; that malarial fevers, Texas cattle fever, and certain forms of dysentery are due to forms of microscopic animal organisms known as microzoa; and for most of these diseases the mode of development and means of introduction of the micro-organism into the body are fairly well understood. To the information thus obtained we owe the triumphs of antiseptic and aseptic surgery, a great increase of precision in diagnosis, the use of specific antitoxins [antidotes to organic infection] as remedies and as preventives, and some of the best practical work in public hygiene.
The evidence as to the increased powers of medicine to give relief from suffering and to prolong life is most clear and direct in the records of modern surgery—particularly in some of its special branches. In a large proportion of certain cases in which the surgeon now operates with a fair chance of success, such as calculus in the kidney or gall-bladder, shot-wounds of the abdomen, and tumours of various kinds, there was no hope in the year 1800, and the unhappy sufferer could only expect a certain, though often a lingering and painful, death. In cases of cancer of the face, tongue, breast, or uterus, the persistent pain, extreme disfigurement, and offensive odors which attended them made death a boon to be prayed for, if not deliberately sought, while now such cases, if brought in time to the surgeon, can often be entirely relieved. The knowledge of this fact has become general with the public, and patients no longer defer an operation as long as possible, as was their custom in days of old. Instead of having to look forward to the torture of incisions, manipulations, and stitching, with but small hope of surviving the exhausting suppuration and blood-poisoning which were such common results, the patient now knows that he will inhale a little sweet vapour, and sleep unconscious of the strokes of the surgeon's knife or the pricks of his needle. He may dream wondrous dreams, but he will soon awake to find himself in his bed staring at the trained nurse standing by his side, and wondering vaguely why the operation has not begun. He does not have to look forward to weeks and even months of daily dressings. The surgeon will glance at his temperature record and at the outside of his bandages, but will probably not touch them for a week; and when he does remove them nothing will be seen but a narrow red line without a trace of suppuration. These improved methods not only preserve the mother for her children, and the bread-winner for the family, but they greatly contribute to the public good by shortening the period of enforced idleness and unproductivity after operations.
Some of the greatest triumphs of modern surgery are obtained in cases of disease or injury of the abdominal organs. The removal of ovarian and uterine tumours is now so common and successful that it is not easy to realize that a hundred years ago there was practically no help or hope for such cases. In former days, the lists of deaths contained many cases reported as inflammation or obstruction of the bowels, or as peritonitis. It is now well understood that most of these cases are due to disease of a little worm-like appendix connected with the large intestine on the right side of the lower part of the abdomen, inflammation of which, known as appendicitis, causes excruciating pain, and often produces internal abscesses and death. An operation for the removal of such a diseased appendix is now common, and in most cases successful. The operation for the removal of calculus, or stone, from the urinary bladder dates from over twenty-five hundred years ago, and no one knows who first performed it. Within the last century it has been largely superseded by an operation which crushes the stone to powder within the bladder, and removes this powder without the use of the knife. The removal of calculi from the kidney or from the gall bladder, and the removal of a diseased kidney, are new operations, made possible by improved means of diagnosis, anæsthesia, and antisepsis [determining disease, causing insensibility, and excluding microbes]. Wounds of the intestines were formerly thought to be almost necessarily fatal, and nothing was done for them except to stupify the patient with opium. Now in such cases the abdomen is opened, the lacerations of the bowel are closed, the effused blood and other matters are removed, and in many cases life has thus been preserved.
By increase of knowledge of the anatomy of the brain, and of the distribution of nerves connected with it, it has become possible in a certain number of cases to determine what part of the brain is suffering from irritation or pressure, and to operate for the removal of the tumour or other substance causing the trouble, with considerable hope of giving permanent relief. A branch of surgery which has developed into an important specialty during the last century is that known as plastic and orthopædic surgery [ameliorating deformities]. The replacing of a lost nose by engrafting other tissue in its place is a very old triumph of surgical art, but operations of this kind have been greatly extended and perfected within the last hundred years, and much can now be done to mitigate the deformity and weakness due to club feet, bandy legs, contracted joints, etc., which formerly were considered to be beyond remedy.
Many of the diseases peculiar to women have been deprived of much of their terrors within a hundred years. In 1800, for every thousand children born, from ten to twenty mothers died. Puerperal fever occurred in epidemics, following certain physicians and nurses, but nothing was known as to its causes or nature. To-day puerperal fever is almost unknown in the hospitals or in the practice of a skilled physician. The death-rate of mothers is less than five per thousand births, and the mechanical obstructions which a century ago would almost certainly have brought about the death of both mother and child, are now so dealt with that more than half of both mothers and children are saved.
The study of the diseases of the eye has greatly developed another specialty during the century, viz., ophthalmology. The investigations of Helmholtz in physiological optics, with his invention of the ophthalmoscope in 1852, effected a revolution in this branch of medical science and art, and have added greatly to human comfort and happiness. A hundred years ago, when the physician saw the eyelids of a new-born babe redden, and swell, and yellow matter ooze from between them, he knew that in a few days or weeks the child would be partially or wholly blind, but he knew nothing of the simple means by which the skilled physician can now prevent such a calamity. It is unfortunately true that this knowledge is not even now sufficiently widely diffused, and that our blind asylums must, for some time to come, continue to receive those that have been deprived of sight during the first months of their life through the ignorance or neglect of those who should have properly cared for them.
While it is certain that the death-rates in the last century were greater than those of the present day, it is not possible to make precise comparisons. The record of deaths in the city of New York begins with 1804, and was necessarily very imperfect until the law of 1851, which required the registration of all deaths; but it shows a death-rate of 30.2 per 1,000 in 1805, which means that the true death-rate must have been between 35 and 40. At present, for a series of five years, it would be about 20, having been below 19 in 1899, so that the death-rate has been diminished by at least one-third. How much of this is due to improved sanitary conditions it is impossible to say. A comparison of the list of causes of death in 1805 with the list of causes for 1900 shows great differences, but much of this is due to changes in name and to more accurate diagnosis.
“Malignant sore throat” and “croup” were well known to anxious parents in 1800, but “diphtheria” caused no anxiety. “Inflammation of the bowels” was common and fatal, but “appendicitis” had not been heard of. “Nervous fever,” “continued fever,” and “low fever” were on the lists, but not typhoid, which was not clearly distinguished as a special form of disease until 1837, when Dr. Gerhard, an American physician, pointed out the differences between it and typhus, which also prevailed at the commencement of the century.
One hundred years ago the great topic of discussion in our cities on the North Atlantic coast was the means of preventing yellow fever, which had been epidemic in New York and Philadelphia for two years. Physicians were disputing as to whether the disease was contagious and imported, and, therefore, perhaps, preventable by quarantine and disinfection, or was due to some occult condition of the atmosphere (which was the view taken by Noah Webster in his “History of Epidemic and Pestilential Diseases,” a work which appeared about the middle of the year 1800, although it is dated 1789). The discussions remind one of the remark that a certain patented form of electric light was surrounded by a cloud of non-luminous verbosity. For example, the Committee of the Medical Society of the State of New York reported that yellow fever may be produced in any country by pestilential effluvia; and Webster concluded that typhus and nervous fevers were due to a “conversion of the perspirable fluids of the body into septic [poisonous] matter”—all of which means that they knew nothing about it. Even now we do not know the cause of yellow fever, or the precise mode of its spread; but we are sufficiently certain that it is due to a specific micro-organism to be confident that its spread can be checked by isolation and disinfection properly applied—and Memphis and New Orleans are witnesses to the truth of this.
In the year 1800, the majority of persons over twenty years old were more or less pitted by small-pox, being the survivors of a much greater number who had suffered from this disease. Dr. Miller in New York had just received from England a thread which had been steeped in the newly discovered vaccine matter, and was about to begin vaccination in this city. To-day there are many physicians who have never seen a case of small-pox, and a face pitted with the marks of this disease is rarely seen.